/*
  Copyright (c) 2012-2014 Open Lab
  Written by Roberto Bicchierai and Silvia Chelazzi http://roberto.open-lab.com
  Permission is hereby granted, free of charge, to any person obtaining
  a copy of this software and associated documentation files (the
  "Software"), to deal in the Software without restriction, including
  without limitation the rights to use, copy, modify, merge, publish,
  distribute, sublicense, and/or sell copies of the Software, and to
  permit persons to whom the Software is furnished to do so, subject to
  the following conditions:

  The above copyright notice and this permission notice shall be
  included in all copies or substantial portions of the Software.

  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/

/**
 * A method to instantiate valid task models from
 * raw data.
*/
function TaskFactory() {
    /**
     * Build a new Task
     */
    this.build = function (id, name, code, level, start, duration, collapsed) {
        // Set at beginning of day
        var adjusted_start = computeStart(start);
        var calculated_end = computeEndByDuration(adjusted_start, duration);

        return new Task(id, name, code, level, adjusted_start, calculated_end, duration, collapsed);
    };
}

function Task(id, name, code, level, start, end, duration, collapsed) {
    this.id = id;
    this.name = name;
    this.progress = 0;
    this.description = "";
    this.code = code;
    this.level = level;
    this.status = "STATUS_UNDEFINED";
    this.depends = "";
    this.canWrite = true; // by default all tasks are writeable

    this.start = start;
    this.duration = duration;
    this.end = end;
    this.startIsMilestone = false;
    this.endIsMilestone = false;

    this.collapsed = collapsed;

    this.rowElement; //row editor html element
    this.ganttElement; //gantt html element
    this.master;

    this.assigs = [];
}

Task.prototype.clone = function () {
    var ret = {};
    for (var key in this) {
        if (typeof (this[key]) != "function") {
            ret[key] = this[key];
        }
    }
    return ret;
};

Task.prototype.getAssigsString = function () {
    var ret = "";
    for (var i = 0; i < this.assigs.length; i++) {
        var ass = this.assigs[i];
        var res = this.master.getResource(ass.resourceId);
        if (res) {
            ret = ret + (ret == "" ? "" : ", ") + res.name;
        }
    }
    return ret;
};

Task.prototype.createAssignment = function (id, resourceId, roleId, effort) {
    var assig = new Assignment(id, resourceId, roleId, effort);
    this.assigs.push(assig);
    return assig;
};

//<%---------- SET PERIOD ---------------------- --%>
Task.prototype.setPeriod = function (start, end) {
    //console.debug("setPeriod ",this.name,new Date(start),new Date(end));
    //var profilerSetPer = new Profiler("gt_setPeriodJS");

    if (start instanceof Date) {
        start = start.getTime();
    }

    if (end instanceof Date) {
        end = end.getTime();
    }

    var originalPeriod = {
        start: this.start,
        end: this.end,
        duration: this.duration
    };

    //console.debug("setStart",date,date instanceof Date);
    var wantedStartMillis = start;

    //cannot start after end
    if (start > end) {
        start = end;
    }

    //set a legal start
    start = computeStart(start);

    //if depends -> start is set to max end + lag of superior
    var sups = this.getSuperiors();
    if (sups && sups.length > 0) {
        var supEnd = 0;
        for (var i = 0; i < sups.length; i++) {
            var link = sups[i];
            supEnd = Math.max(supEnd, incrementDateByWorkingDays(link.from.end, link.lag));
        }
        //if changed by depends move it
        if (computeStart(supEnd) != start) {
            return this.moveTo(supEnd + 1, false);
        }
    }

    var somethingChanged = false;

    //move date to closest day
    var date = new Date(start);

    if (this.start != start || this.start != wantedStartMillis) {
        this.start = start;
        somethingChanged = true;
    }

    //set end
    var wantedEndMillis = end;
    end = computeEnd(end);

    if (this.end != end || this.end != wantedEndMillis) {
        this.end = end;
        somethingChanged = true;
    }

    this.duration = recomputeDuration(this.start, this.end);

    //profilerSetPer.stop();

    //nothing changed exit
    if (!somethingChanged)
        return true;

    //cannot write exit
    if (!this.canWrite) {
        this.master.setErrorOnTransaction(GanttMaster.messages["CANNOT_WRITE"] + "\n" + this.name, this);
        return false;
    }

    //external dependencies: exit with error
    if (this.hasExternalDep) {
        this.master.setErrorOnTransaction(GanttMaster.messages["TASK_HAS_EXTERNAL_DEPS"] + "\n" + this.name, this);
        return false;
    }

    var todoOk = true;

    //I'm restricting
    var deltaPeriod = originalPeriod.duration - this.duration;
    var restricting = deltaPeriod > 0;
    var restrictingStart = restricting && (originalPeriod.start < this.start);
    var restrictingEnd = restricting && (originalPeriod.end > this.end);

    //console.debug( " originalPeriod.duration "+ originalPeriod.duration +" deltaPeriod "+deltaPeriod+" "+"restricting "+restricting);

    if (restricting) {
        //loops children to get boundaries
        var children = this.getChildren();
        var bs = Infinity;
        var be = 0;
        for (var i = 0; i < children.length; i++) {
            ch = children[i];
            //console.debug("restricting: test child "+ch.name+" "+ch.end)
            if (restrictingEnd) {
                be = Math.max(be, ch.end);
            } else {
                bs = Math.min(bs, ch.start);
            }
        }

        if (restrictingEnd) {
            //console.debug("restricting end ",be, this.end);
            this.end = Math.max(be, this.end);
        } else {
            //console.debug("restricting start");
            this.start = Math.min(bs, this.start);
        }

        this.duration = recomputeDuration(this.start, this.end);
    } else {
        //check global boundaries
        if (this.start < this.master.minEditableDate || this.end > this.master.maxEditableDate) {
            this.master.setErrorOnTransaction(GanttMaster.messages["CHANGE_OUT_OF_SCOPE"], this);
            todoOk = false;
        }

        //console.debug("set period: somethingChanged",this);
        if (todoOk && !updateTree(this)) {
            todoOk = false;
        }
    }

    if (todoOk) {
        //and now propagate to inferiors
        var infs = this.getInferiors();
        if (infs && infs.length > 0) {
            for (var i = 0; i < infs.length; i++) {
                var link = infs[i];
                if (!link.to.canWrite) {
                    this.master.setErrorOnTransaction(GanttMaster.messages["CANNOT_WRITE"] + "\n" + link.to.name, link.to);
                    break;
                }
                todoOk = link.to.moveTo(end, false); //this is not the right date but moveTo checks start
                if (!todoOk)
                    break;
            }
        }
    }

    return todoOk;
};

//<%---------- MOVE TO ---------------------- --%>
Task.prototype.moveTo = function (start, ignoreMilestones) {
    //console.debug("moveTo ",this,start,ignoreMilestones);
    //var profiler = new Profiler("gt_task_moveTo");

    if (start instanceof Date) {
        start = start.getTime();
    }

    var originalPeriod = {
        start: this.start,
        end: this.end
    };

    var wantedStartMillis = start;

    //set a legal start
    start = computeStart(start);

    //if start is milestone cannot be move
    if (!ignoreMilestones && this.startIsMilestone && start != this.start) {
        //notify error
        this.master.setErrorOnTransaction(GanttMaster.messages["START_IS_MILESTONE"], this);
        return false;
    } else if (this.hasExternalDep) {
        //notify error
        this.master.setErrorOnTransaction(GanttMaster.messages["TASK_HAS_EXTERNAL_DEPS"], this);
        return false;
    }

    //if depends start is set to max end + lag of superior
    var sups = this.getSuperiors();
    if (sups && sups.length > 0) {
        var supEnd = 0;
        for (var i = 0; i < sups.length; i++) {
            var link = sups[i];
            supEnd = Math.max(supEnd, incrementDateByWorkingDays(link.from.end, link.lag));
        }
        start = supEnd + 1;
    }
    //set a legal start
    start = computeStart(start);

    var end = computeEndByDuration(start, this.duration);

    if (this.start != start || this.start != wantedStartMillis) {
        //in case of end is milestone it never changes, but recompute duration
        if (!ignoreMilestones && this.endIsMilestone) {
            end = this.end;
            this.duration = recomputeDuration(start, end);
        }
        this.start = start;
        this.end = end;
        //profiler.stop();

        //check global boundaries
        if (this.start < this.master.minEditableDate || this.end > this.master.maxEditableDate) {
            this.master.setErrorOnTransaction(GanttMaster.messages["CHANGE_OUT_OF_SCOPE"], this);
            return false;
        }

        var panDelta = originalPeriod.start - this.start;
        //console.debug("panDelta",panDelta);
        //loops children to shift them
        var children = this.getChildren();
        for (var i = 0; i < children.length; i++) {
            ch = children[i];
            if (!ch.moveTo(ch.start - panDelta, false)) {
                return false;
            }
        }

        //console.debug("set period: somethingChanged",this);
        if (!updateTree(this)) {
            return false;
        }

        //and now propagate to inferiors
        var infs = this.getInferiors();
        if (infs && infs.length > 0) {
            for (var i = 0; i < infs.length; i++) {
                var link = infs[i];

                //this is not the right date but moveTo checks start
                if (!link.to.canWrite) {
                    this.master.setErrorOnTransaction(GanttMaster.messages["CANNOT_WRITE"] + "\n" + link.to.name, link.to);
                } else if (!link.to.moveTo(end, false)) {
                    return false;
                }
            }
        }
    }

    return true;
};

function updateTree(task) {
    //console.debug("updateTree ",task);
    var error;

    //try to enlarge parent
    var p = task.getParent();

    //no parent:exit
    if (!p)
        return true;

    var newStart = p.start;
    var newEnd = p.end;

    if (p.start > task.start) {
        if (p.startIsMilestone) {
            task.master.setErrorOnTransaction(GanttMaster.messages["START_IS_MILESTONE"] + "\n" + p.name, task);
            return false;
        } else if (p.depends) {
            task.master.setErrorOnTransaction(GanttMaster.messages["TASK_HAS_CONSTRAINTS"] + "\n" + p.name, task);
            return false;
        }

        newStart = task.start;
    }

    if (p.end < task.end) {
        if (p.endIsMilestone) {
            task.master.setErrorOnTransaction(GanttMaster.messages["END_IS_MILESTONE"] + "\n" + p.name, task);
            return false;
        }

        newEnd = task.end;
    }

    //propagate updates if needed
    if (newStart != p.start || newEnd != p.end) {
        //can write?
        if (!p.canWrite) {
            task.master.setErrorOnTransaction(GanttMaster.messages["CANNOT_WRITE"] + "\n" + p.name, task);
            return false;
        }

        //has external deps ?
        if (p.hasExternalDep) {
            task.master.setErrorOnTransaction(GanttMaster.messages["TASK_HAS_EXTERNAL_DEPS"] + "\n" + p.name, task);
            return false;
        }

        return p.setPeriod(newStart, newEnd);
    }

    return true;
}

//<%---------- CHANGE STATUS ---------------------- --%>
Task.prototype.changeStatus = function (newStatus) {
    //console.debug("changeStatus: "+this.name+" from "+this.status+" -> "+newStatus);
    //compute descendant for identify a cone where status changes propagate
    var cone = this.getDescendant();

    function propagateStatus(task, newStatus, manuallyChanged, propagateFromParent, propagateFromChildren) {
        //console.debug("propagateStatus",task.name, task.status,newStatus)
        var oldStatus = task.status;

        //no changes exit
        if (newStatus == oldStatus) {
            return true;
        }
        //console.debug("propagateStatus: "+task.name + " from " + task.status + " to " + newStatus + " " + (manuallyChanged?" a manella":"")+(propagateFromParent?" da parent":"")+(propagateFromChildren?" da children":""));

        var todoOk = true;
        task.status = newStatus;

        if (task.master.cannotCloseTaskIfIssueOpen && newStatus == "STATUS_DONE" && task.openIssues > 0) {
            task.master.setErrorOnTransaction(GanttMaster.messages["CANNOT_CLOSE_TASK_IF_OPEN_ISSUE"] + " " + task.name);
            return false;
        }

        //xxxx -> STATUS_DONE            may activate dependent tasks, both suspended and undefined. Will set to done all descendants.
        //STATUS_FAILED -> STATUS_DONE          do nothing if not forced by hand
        if (newStatus == "STATUS_DONE") {
            if ((manuallyChanged || oldStatus != "STATUS_FAILED")) { //cannot change for cascade when failed
                //can be closed only if superiors are already done
                var sups = task.getSuperiors();
                for (var i = 0; i < sups.length; i++) {
                    if (cone.indexOf(sups[i].from) < 0) {
                        if (sups[i].from.status != "STATUS_DONE") {
                            if (manuallyChanged || propagateFromParent)
                                task.master.setErrorOnTransaction(GanttMaster.messages["GANTT_ERROR_DEPENDS_ON_OPEN_TASK"] + "\n" + sups[i].from.name + " -> " + task.name);
                            todoOk = false;
                            break;
                        }
                    }
                }

                if (todoOk) {
                    //todo set progress to 100% if set on config

                    var chds = task.getChildren();
                    //set children as done
                    for (var i = 0; i < chds.length; i++)
                        propagateStatus(chds[i], "STATUS_DONE", false, true, false);

                    //set inferiors as active if outside the cone
                    propagateToInferiors(cone, task.getInferiors(), "STATUS_ACTIVE");
                }
            } else {
                todoOk = false;
            }

            //  STATUS_UNDEFINED -> STATUS_ACTIVE       all children become active, if they have no dependencies.
            //  STATUS_SUSPENDED -> STATUS_ACTIVE       sets to active all children and their descendants that have no inhibiting dependencies.
            //  STATUS_DONE -> STATUS_ACTIVE            all those that have dependencies must be set to suspended.
            //  STATUS_FAILED -> STATUS_ACTIVE          nothing happens: child statuses must be reset by hand.
        } else if (newStatus == "STATUS_ACTIVE") {
            if ((manuallyChanged || oldStatus != "STATUS_FAILED")) { //cannot change for cascade when failed
                //activate parent if closed
                var par = task.getParent();
                if (par && par.status != "STATUS_ACTIVE") {
                    todoOk = propagateStatus(par, "STATUS_ACTIVE", false, false, true);
                }

                if (todoOk) {
                    //can be active only if superiors are already done
                    var sups = task.getSuperiors();
                    for (var i = 0; i < sups.length; i++) {
                        if (sups[i].from.status != "STATUS_DONE") {
                            if (manuallyChanged || propagateFromChildren)
                                task.master.setErrorOnTransaction(GanttMaster.messages["GANTT_ERROR_DEPENDS_ON_OPEN_TASK"] + "\n" + sups[i].from.name + " -> " + task.name);
                            todoOk = false;
                            break;
                        }
                    }
                }

                if (todoOk) {
                    var chds = task.getChildren();
                    if (oldStatus == "STATUS_UNDEFINED" || oldStatus == "STATUS_SUSPENDED") {
                        //set children as active
                        for (var i = 0; i < chds.length; i++)
                            if (chds[i].status != "STATUS_DONE")
                                propagateStatus(chds[i], "STATUS_ACTIVE", false, true, false);
                    }

                    //set inferiors as suspended
                    var infs = task.getInferiors();
                    for (var i = 0; i < infs.length; i++)
                        propagateStatus(infs[i].to, "STATUS_SUSPENDED", false, false, false);
                }
            } else {
                todoOk = false;
            }

            // xxxx -> STATUS_SUSPENDED       all active children and their active descendants become suspended. when not failed or forced
            // xxxx -> STATUS_UNDEFINED       all active children and their active descendants become suspended. when not failed or forced
        } else if (newStatus == "STATUS_SUSPENDED" || newStatus == "STATUS_UNDEFINED") {
            if (manuallyChanged || oldStatus != "STATUS_FAILED") { //cannot change for cascade when failed
                //suspend parent if not active
                var par = task.getParent();
                if (par && par.status != "STATUS_ACTIVE") {
                    todoOk = propagateStatus(par, newStatus, false, false, true);
                }

                var chds = task.getChildren();
                //set children as active
                for (var i = 0; i < chds.length; i++) {
                    if (chds[i].status != "STATUS_DONE")
                        propagateStatus(chds[i], newStatus, false, true, false);
                }

                //set inferiors as STATUS_SUSPENDED or STATUS_UNDEFINED
                propagateToInferiors(cone, task.getInferiors(), newStatus);
            } else {
                todoOk = false;
            }

            // xxxx -> STATUS_FAILED children and dependent failed
        } else if (newStatus == "STATUS_FAILED") {
            var chds = task.getChildren();
            //set children as failed
            for (var i = 0; i < chds.length; i++)
                propagateStatus(chds[i], "STATUS_FAILED", false, true, false);

            //set inferiors as active
            //set children as done
            propagateToInferiors(cone, task.getInferiors(), "STATUS_FAILED");
        }
        if (!todoOk) {
            task.status = oldStatus;
            //console.debug("status rolled back: "+task.name + " to " + oldStatus);
        }

        return todoOk;
    }

    /**
     * A helper method to traverse an array of 'inferior' tasks
     * and signal a status change.
     */
    function propagateToInferiors(cone, infs, status) {
        for (var i = 0; i < infs.length; i++) {
            if (cone.indexOf(infs[i].to) < 0) {
                propagateStatus(infs[i].to, status, false, false, false);
            }
        }
    }

    var todoOk = true;
    var oldStatus = this.status;

    todoOk = propagateStatus(this, newStatus, true, false, false);

    if (!todoOk)
        this.status = oldStatus;

    return todoOk;
};

Task.prototype.synchronizeStatus = function () {
    var oldS = this.status;
    this.status = "";
    return this.changeStatus(oldS);
};

Task.prototype.isLocallyBlockedByDependencies = function () {
    var sups = this.getSuperiors();
    var blocked = false;
    for (var i = 0; i < sups.length; i++) {
        if (sups[i].from.status != "STATUS_DONE") {
            blocked = true;
            break;
        }
    }
    return blocked;
};

//<%---------- TASK STRUCTURE ---------------------- --%>
Task.prototype.getRow = function () {
    ret = -1;
    if (this.master)
        ret = this.master.tasks.indexOf(this);
    return ret;
};

Task.prototype.getParents = function () {
    var ret;
    if (this.master) {
        var topLevel = this.level;
        var pos = this.getRow();
        ret = [];
        for (var i = pos; i >= 0; i--) {
            var par = this.master.tasks[i];
            if (topLevel > par.level) {
                topLevel = par.level;
                ret.push(par);
            }
        }
    }
    return ret;
};

Task.prototype.getParent = function () {
    var ret;
    if (this.master) {
        for (var i = this.getRow() ; i >= 0; i--) {
            var par = this.master.tasks[i];
            if (this.level > par.level) {
                ret = par;
                break;
            }
        }
    }
    return ret;
};

Task.prototype.isParent = function () {
    var ret = false;
    if (this.master) {
        var pos = this.getRow();
        if (pos < this.master.tasks.length - 1)
            ret = this.master.tasks[pos + 1].level > this.level;
    }
    return ret;
};

Task.prototype.getChildren = function () {
    var ret = [];
    if (this.master) {
        var pos = this.getRow();
        for (var i = pos + 1; i < this.master.tasks.length; i++) {
            var ch = this.master.tasks[i];
            if (ch.level == this.level + 1)
                ret.push(ch);
            else if (ch.level <= this.level) // exit loop if parent or brother
                break;
        }
    }
    return ret;
};

Task.prototype.getDescendant = function () {
    var ret = [];
    if (this.master) {
        var pos = this.getRow();
        for (var i = pos + 1; i < this.master.tasks.length; i++) {
            var ch = this.master.tasks[i];
            if (ch.level > this.level)
                ret.push(ch);
            else
                break;
        }
    }
    return ret;
};

Task.prototype.getSuperiors = function () {
    var ret = [];
    var task = this;
    if (this.master) {
        ret = this.master.links.filter(function (link) {
            return link.to == task;
        });
    }
    return ret;
};

Task.prototype.getSuperiorTasks = function () {
    var ret = [];
    var sups = this.getSuperiors();
    for (var i = 0; i < sups.length; i++)
        ret.push(sups[i].from);
    return ret;
};

Task.prototype.getInferiors = function () {
    var ret = [];
    var task = this;
    if (this.master) {
        ret = this.master.links.filter(function (link) {
            return link.from == task;
        });
    }
    return ret;
};

Task.prototype.getInferiorTasks = function () {
    var ret = [];
    var infs = this.getInferiors();
    for (var i = 0; i < infs.length; i++)
        ret.push(infs[i].to);
    return ret;
};

Task.prototype.deleteTask = function () {
    //delete both dom elements
    this.rowElement.remove();
    this.ganttElement.remove();

    //remove children
    var chd = this.getChildren();
    for (var i = 0; i < chd.length; i++) {
        //add removed child in list
        if (!chd[i].isNew())
            this.master.deletedTaskIds.push(chd[i].id);
        chd[i].deleteTask();
    }

    if (!this.isNew())
        this.master.deletedTaskIds.push(this.id);

    //remove from in-memory collection
    this.master.tasks.splice(this.getRow(), 1);

    //remove from links
    var task = this;
    this.master.links = this.master.links.filter(function (link) {
        return link.from != task && link.to != task;
    });
};

Task.prototype.isNew = function () {
    return (this.id + "").indexOf("tmp_") == 0;
};

Task.prototype.isDependent = function (t) {
    //console.debug("isDependent",this.name, t.name)
    var task = this;
    var dep = this.master.links.filter(function (link) {
        return link.from == task;
    });

    // is t a direct dependency?
    for (var i = 0; i < dep.length; i++) {
        if (dep[i].to == t)
            return true;
    }
    // is t an indirect dependency
    for (var i = 0; i < dep.length; i++) {
        if (dep[i].to.isDependent(t)) {
            return true;
        }
    }
    return false;
};

Task.prototype.setLatest = function (maxCost) {
    this.latestStart = maxCost - this.criticalCost;
    this.latestFinish = this.latestStart + this.duration;
};

//<%------------------------------------------  INDENT/OUTDENT --------------------------------%>
Task.prototype.indent = function () {
    //console.debug("indent", this);
    //a row above must exist
    var row = this.getRow();

    //no row no party
    if (row <= 0)
        return false;

    var ret = false;
    var taskAbove = this.master.tasks[row - 1];
    var newLev = this.level + 1;
    if (newLev <= taskAbove.level + 1) {
        ret = true;
        //trick to get parents after indent
        this.level++;
        var futureParents = this.getParents();
        this.level--;
        var oldLevel = this.level;
        for (var i = row; i < this.master.tasks.length; i++) {
            var desc = this.master.tasks[i];
            if (desc.level > oldLevel || desc == this) {
                desc.level++;
                //remove links from descendant to my parents
                this.master.links = this.master.links.filter(function (link) {
                    var linkToParent = false;
                    if (link.to == desc)
                        linkToParent = futureParents.indexOf(link.from) >= 0;
                    else if (link.from == desc)
                        linkToParent = futureParents.indexOf(link.to) >= 0;
                    return !linkToParent;
                });
            } else
                break;
        }

        var parent = this.getParent();
        // set start date to parent' start if no deps
        if (parent && !this.depends) {
            var new_end = computeEndByDuration(parent.start, this.duration);
            this.master.changeTaskDates(this, parent.start, new_end);
        }
        //TODO:������ ��code�Զ��γɲ㼶����
        if (this.master.isLevelCode) {
            this.master.levelCode();
        }
        //recompute depends string
        this.master.updateDependsStrings();
        //enlarge parent using a fake set period
        this.setPeriod(this.start + 1, this.end + 1);

        //force status check
        this.synchronizeStatus();
    }
    return ret;
};

Task.prototype.outdent = function () {
    //console.debug("outdent", this);

    //a level must be >1 -> cannot escape from root
    if (this.level <= 1)
        return false;

    var ret = false;
    var oldLevel = this.level;

    ret = true;
    var row = this.getRow();
    for (var i = row; i < this.master.tasks.length; i++) {
        var desc = this.master.tasks[i];
        if (desc.level > oldLevel || desc == this) {
            desc.level--;
        } else
            break;
    }

    var task = this;
    var chds = this.getChildren();
    //remove links from me to my new children
    this.master.links = this.master.links.filter(function (link) {
        var linkExist = (link.to == task && chds.indexOf(link.from) >= 0 || link.from == task && chds.indexOf(link.to) >= 0);
        return !linkExist;
    });

    //enlarge me if inherited children are larger
    for (var i = 0; i < chds.length; i++) {
        //remove links from me to my new children
        chds[i].setPeriod(chds[i].start + 1, chds[i].end + 1);
    }
    //TODO:������ ��code�Զ��γɲ㼶����
    if (this.master.isLevelCode) {
        this.master.levelCode();
    }
    //recompute depends string
    this.master.updateDependsStrings();

    //enlarge parent using a fake set period
    this.setPeriod(this.start + 1, this.end + 1);

    //force status check
    this.synchronizeStatus();
    return ret;
};

//<%------------------------------------------  MOVE UP / MOVE DOWN --------------------------------%>
Task.prototype.moveUp = function () {
    //console.debug("moveUp", this);
    var ret = false;

    //a row above must exist
    var row = this.getRow();

    //no row no party
    if (row <= 0)
        return false;

    //find new row
    var newRow;
    for (newRow = row - 1; newRow >= 0; newRow--) {
        if (this.master.tasks[newRow].level <= this.level)
            break;
    }

    //is a parent or a brother
    if (this.master.tasks[newRow].level == this.level) {
        ret = true;
        //compute descendant
        var descNumber = 0;
        for (var i = row + 1; i < this.master.tasks.length; i++) {
            var desc = this.master.tasks[i];
            if (desc.level > this.level) {
                descNumber++;
            } else {
                break;
            }
        }
        //move in memory
        var blockToMove = this.master.tasks.splice(row, descNumber + 1);
        var top = this.master.tasks.splice(0, newRow);
        this.master.tasks = [].concat(top, blockToMove, this.master.tasks);
        //move on dom
        var rows = this.master.editor.element.find("tr[taskId]");
        var domBlockToMove = rows.slice(row, row + descNumber + 1);
        rows.eq(newRow).before(domBlockToMove);
        //TODO:������ ��code�Զ��γɲ㼶����
        if (this.master.isLevelCode) {
            this.master.levelCode();
        }
        //recompute depends string
        this.master.updateDependsStrings();
    } else {
        this.master.setErrorOnTransaction(GanttMaster.messages["TASK_MOVE_INCONSISTENT_LEVEL"], this);
        ret = false;
    }
    return ret;
};

Task.prototype.moveDown = function () {
    //console.debug("moveDown", this);

    //a row below must exist, and cannot move root task
    var row = this.getRow();
    if (row >= this.master.tasks.length - 1 || row == 0)
        return false;

    var ret = false;

    //find nearest brother
    var newRow;
    for (newRow = row + 1; newRow < this.master.tasks.length; newRow++) {
        if (this.master.tasks[newRow].level <= this.level)
            break;
    }

    //is brother
    if (this.master.tasks[newRow] && this.master.tasks[newRow].level == this.level) {
        ret = true;
        //find last desc
        for (newRow = newRow + 1; newRow < this.master.tasks.length; newRow++) {
            if (this.master.tasks[newRow].level <= this.level)
                break;
        }

        //compute descendant
        var descNumber = 0;
        for (var i = row + 1; i < this.master.tasks.length; i++) {
            var desc = this.master.tasks[i];
            if (desc.level > this.level) {
                descNumber++;
            } else {
                break;
            }
        }

        //move in memory
        var blockToMove = this.master.tasks.splice(row, descNumber + 1);
        var top = this.master.tasks.splice(0, newRow - descNumber - 1);
        this.master.tasks = [].concat(top, blockToMove, this.master.tasks);

        //move on dom
        var rows = this.master.editor.element.find("tr[taskId]");
        var aft = rows.eq(newRow - 1);
        var domBlockToMove = rows.slice(row, row + descNumber + 1);
        aft.after(domBlockToMove);
        //TODO:������ ��code�Զ��γɲ㼶����
        if (this.master.isLevelCode) {
            this.master.levelCode();
        }
        //recompute depends string
        this.master.updateDependsStrings();
    }

    return ret;
};

//<%------------------------------------------------------------------------  LINKS OBJECT ---------------------------------------------------------------%>
function Link(taskFrom, taskTo, lagInWorkingDays) {
    this.from = taskFrom;
    this.to = taskTo;
    this.lag = lagInWorkingDays;
}

//<%------------------------------------------------------------------------  ASSIGNMENT ---------------------------------------------------------------%>
function Assignment(id, resourceId, roleId, effort) {
    this.id = id;
    this.resourceId = resourceId;
    this.roleId = roleId;
    this.effort = effort;
}

//<%------------------------------------------------------------------------  RESOURCE ---------------------------------------------------------------%>
function Resource(id, name) {
    this.id = id;
    this.name = name;
}

//<%------------------------------------------------------------------------  ROLE ---------------------------------------------------------------%>
function Role(id, name) {
    this.id = id;
    this.name = name;
}